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TOEPLITZ OPERATORS BETWEEN WEIGHTED BERGMAN SPACES OVER THE HALF-PLANE
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作者 Lixia FENG Yan LI +1 位作者 Zhiyu WANG Liankuo ZHAO 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1707-1720,共14页
In this paper,by characterizing Carleson measures,we investigate a class of bounded Toeplitz operator between weighted Bergman spaces with Békolléweights over the half-plane for all index choices.
关键词 weighted bergman spaces békolléweights Carleson measure Toeplitz operators
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MAGiC技术联合超高b值DWI对宫颈癌宫旁浸润诊断的价值
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作者 陈婷婷 陈志健 +3 位作者 张丽 陈敏兰 彭晓澜 苏裕盛 《磁共振成像》 北大核心 2025年第1期140-145,共6页
目的探讨磁共振集成(magnetic resonance image complication,MAGiC)序列联合超高b值磁共振扩散加强成像(ultra-high b-value diffusion weighted imaging,uh-DWI)在宫颈癌宫旁浸润诊断中的价值。材料与方法回顾性分析宁德师范学院附属... 目的探讨磁共振集成(magnetic resonance image complication,MAGiC)序列联合超高b值磁共振扩散加强成像(ultra-high b-value diffusion weighted imaging,uh-DWI)在宫颈癌宫旁浸润诊断中的价值。材料与方法回顾性分析宁德师范学院附属宁德市医院2022年8月至2024年4月经手术病理证实的40例宫颈癌患者,根据病理结果是否有宫旁浸润分为浸润阴性(阴性组)和浸润阳性(阳性组),所有受试者均行MAGiC和uh-DWI序列,并测量肿瘤纵向弛豫值(T1值)、横向弛豫值(T2值)、质子密度(proton density,PD)值和超高b值表观扩散系数(ultra-high apparent diffusion coefficient,ADCuh)。使用Mann-Whiney U检验比较阴性组与阳性组各参数值。使用受试者工作特征(receiver operating characteristic,ROC)曲线评价各单一定量参数,并将差异有统计学意义的参数联合评价宫颈癌宫旁浸润的诊断效能。结果阳性组T1值、T2值均低于阴性组,差异有统计学意义(P<0.001),PD值在两组间差异无统计学意义(P=0.141),阳性组ADCuh值低于阴性组(P<0.001),T1、T2和ADCuh区分宫颈癌宫旁浸润的ROC曲线下面积(area under the curve,AUC)分别为0.899(95%CI:0.762~0.972)、0.962(95%CI:0.849~0.997)、0.934(95%CI:0.809~0.988),敏感度、特异度分别为86.36%、77.80%,100.00%、77.78%和77.27%、94.44%。三者联合鉴别宫旁浸润的AUC最高,为0.985,敏感度为100.00%,特异度为95.40%。结论MAGiC联合uh-DWI有助于判断宫颈癌宫旁浸润,综合运用多参数各优势并联合有差异的参数可获得良好的宫旁浸润的诊断效能。 展开更多
关键词 宫颈癌 宫旁浸润 磁共振集成 超高b值扩散加权成像 多参数联合 磁共振成像
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眼眶弥漫性大B细胞淋巴瘤的病理学与磁共振成像特征研究
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作者 朱红娜 曲晓瑜 +2 位作者 王昞 陆慧琴 苏安乐 《实用临床医药杂志》 CAS 2024年第22期46-51,共6页
目的探讨眼眶弥漫性大B细胞淋巴瘤(DLBCL)的病理学特征与磁共振成像(MRI)特征。方法采用回顾性病例对照研究方法,选取48例眼眶DLBCL患者纳入眼眶DLBCL组,另选取同期51例原发性中枢神经系统DLBCL患者纳入原发性DLBCL组。分析眼眶DLBCL组... 目的探讨眼眶弥漫性大B细胞淋巴瘤(DLBCL)的病理学特征与磁共振成像(MRI)特征。方法采用回顾性病例对照研究方法,选取48例眼眶DLBCL患者纳入眼眶DLBCL组,另选取同期51例原发性中枢神经系统DLBCL患者纳入原发性DLBCL组。分析眼眶DLBCL组患者的临床特征和MRI影像学特征,并比较2组患者的病理学特征和外周血中血小板与淋巴细胞比值(PLR)、中性粒细胞与淋巴细胞比值(NLR)和淋巴细胞与单核细胞比值(LMR)。结果眼眶DLBCL患者的主要临床表现包括眼局部肿块48例(100.00%)、眼球活动受限38例(79.17%)、眼球突出33例(68.75%)、视力下降25例(52.08%)、复视17例(35.42%)和鼻出血9例(18.75%);眼眶DLBCL好发于肌锥外间隙(54.17%),病变多位于眼眶上方(52.08%),T1加权像主要表现为中等信号(60.42%),T2加权像主要表现为中等信号(56.25%)和高信号(29.17%),扩散加权成像主要表现为高信号(58.33%),表观扩散系数图主要表现为低信号(60.42%)。2组患者在病理组织学分型、CD20阳性表达、CD79a阳性表达、CD45RO阳性表达、国际预后指数评分、病理学分期方面比较,差异均无统计学意义(P>0.05);眼眶DLBCL组患者外周血PLR高于原发性DLBCL组,NLR、LMR低于原发性DLBCL组,差异均有统计学意义(P<0.05)。结论眼眶DLBCL具有特异性的临床表现和MRI特征,MRI可作为其主要诊断手段,结合病理学免疫组化分析及外周血PLR、NLR、LMR检测结果,有助于提高诊断的准确性和及时性。 展开更多
关键词 眼眶 弥漫性大b细胞淋巴瘤 磁共振成像 病理学 免疫组化 T2加权像
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Importance of b value in diffusion weighted imaging for the diagnosis of pancreatic cancer 被引量:12
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作者 Jin-Gang Hao Jia-Ping Wang +1 位作者 Ya-Lv Gu Ming-Liang Lu 《World Journal of Gastroenterology》 SCIE CAS 2013年第39期6651-6655,共5页
AIM:To investigate the use of multi-b-value diffusionweighted imaging in diagnosing pancreatic cancer.METHODS:We retrospectively analyzed 33 cases of pancreatic cancer and 12 cases of benign pancreatic tumors at the S... AIM:To investigate the use of multi-b-value diffusionweighted imaging in diagnosing pancreatic cancer.METHODS:We retrospectively analyzed 33 cases of pancreatic cancer and 12 cases of benign pancreatic tumors at the Second Affiliated Hospital of Kunming Medical University from December 2008 to January2011.The demographic characteristics,clinical presentation,routine magnetic resonance imaging and diffusion weighted imaging(DWI)features with different b values were reviewed.Continuous data were expressed as mean±SD.Comparisons between pancreatic cancer and benign pancreatic tumors were performed using the Student’s t test.A probability of P<0.05 was considered statistically significant.RESULTS:Thirty-three patients with pancreatic cancer were identified.The mean age at diagnosis was 60±5.6 years.The male:female ratio was 21:12.Twenty cases were confirmed by surgical resection and 13 by biopsy of metastases.T1 weighted images demonstrated a pancreatic head mass in 16 patients,a pancreatic body mass in 10 cases,and a pancreatic tail mass with pancreatic atrophy in 7 cases.Eight patients had hepatic metastases,13 had invasion or envelopment of mesenteric vessels,4 had bone metastases,and 8had lymph node metastases.DWI demonstrated an irregular intense mass with unclear margins.Necrotic tissue demonstrated an uneven low signal.A b of 1100s/mm2was associated with a high intensity signal with poor anatomical delineation.A b of 700 s/mm2was associated with apparent diffusion coefficients(ADCs)that were useful in distinguishing benign and malignant pancreatic tumors(P<0.05).b values of 50,350,400,450 and 1100 s/mm2were associated with ADCs that did not differentiate the two tumors.CONCLUSION:Low b value images demonstrated superior anatomical details when compared to high b value images.Tumor tissue definition was high and contrast with the surrounding tissues was good.DWI was useful in diagnosing pancreatic cancer. 展开更多
关键词 PANCREATIC cancer Magnetic resonance IMAGING b value APPARENT DIFFUSION coefficient DIFFUSION weighted IMAGING
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高场磁共振多b值弥散加权成像对肝细胞癌与肝血管瘤的鉴别诊断价值分析
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作者 郭凯 孙勇 +1 位作者 杨明 丁会 《实用癌症杂志》 2024年第12期2048-2051,共4页
目的分析高场磁共振(MRI)多b值弥散加权成像(DWI)对肝细胞癌与肝血管瘤中的鉴别诊断价值。方法选取行高场MRI-DWI检查的109例患者,所有患者病情经病理检查明晰,43例肝细胞癌患者划入观察组,66例肝血管瘤患者划入对照组,对比两组不同b值... 目的分析高场磁共振(MRI)多b值弥散加权成像(DWI)对肝细胞癌与肝血管瘤中的鉴别诊断价值。方法选取行高场MRI-DWI检查的109例患者,所有患者病情经病理检查明晰,43例肝细胞癌患者划入观察组,66例肝血管瘤患者划入对照组,对比两组不同b值下的表观弥散系数(ADC)值;另绘制受试者工作曲线(ROC),分析不同b值下ADC值鉴别诊断肝细胞癌与肝血管瘤的效能。结果b值为50 s/mm^(2)、400 s/mm^(2)、1000 s/mm^(2)时,观察组的ADC值分别为(2.09±0.42)×10^(-3)/mm^(2)/s、(1.72±0.36)×10^(-3)/mm^(2)/s、(1.39±0.28)×10^(-3)/mm^(2)/s,均低于对照组的(2.45±0.57)×10^(-3)/mm^(2)/s、(2.16±0.45)×10^(-3)/mm^(2)/s、(1.88±0.47)×10^(-3)/mm^(2)/s,有统计学差异(P<0.05);ROC结果显示:当b值在1000 s/mm^(2)时,ADC值鉴别诊断肝细胞癌与肝血管瘤的曲线下面积(AUC)、敏感度、特异度最高,分别为0.816、90.70%、72.70%。结论高场MRI-DWI能够有效鉴别诊断出肝细胞癌与肝血管瘤,且b值越大,诊断效果越强,具有一定的应用价值。 展开更多
关键词 肝细胞癌 肝血管瘤 高场磁共振多b值弥散加权成像 诊断
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Influence of weight management on the prognosis of steatohepatitis in chronic hepatitis B patients during antiviral treatment 被引量:15
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作者 Xiu-Juan Chang Yi-Wen Shi +19 位作者 Jing Wang Hua-Bao Liu Yan Chen Xiao-Ning Zhu Yong-Ping Chen Zu-Jiang Yu Qing-Hua Shang Lin Tan Qin Li Li Jiang Guang-Ming Xiao Liang Chen Wei Lu Xiao-Yu Hu Qing-Hua Long Lin-Jing An Zi-Yuan Zou Vincent Wai-Sun Wong Yong-Ping Yang Jian-Gao Fan 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2021年第5期416-425,共10页
Background:Although concomitant nonalcoholic steatohepatitis(NASH)is common in chronic hepatitis B(CHB),the impact of viral factors on NASH and the outcome of CHB patients concomitant with NASH remain unclear.We aimed... Background:Although concomitant nonalcoholic steatohepatitis(NASH)is common in chronic hepatitis B(CHB),the impact of viral factors on NASH and the outcome of CHB patients concomitant with NASH remain unclear.We aimed to investigate the outcomes of NASH in CHB patients receiving antiviral treatment.Methods:In the post-hoc analysis of a multicenter trial,na?ve CHB patients receiving 72-week entecavir treatment were enrolled.We evaluated the biochemical,viral and histopathological responses of these patients.The histopathological features of NASH were also evaluated,using paired liver biopsies at baseline and week 72.Results:A total of 1000 CHB patients were finally enrolled for analysis,with 18.2%of whom fulfilling the criteria of NASH.A total of 727 patients completed entecavir antiviral treatment and received the second biopsy.Serum HBe Ag loss,HBe Ag seroconversion and HBV-DNA undetectable rates were similar between patients with or without NASH(P>0.05).Among patients with NASH,the hepatic steatosis,ballooning,lobular inflammation scores and fibrosis stages all improved during follow-up(all P<0.001),46%(63/136)achieved NASH resolution.Patients with baseline body mass index(BMI)≥23 kg/m2(Asian criteria)[odds ratio(OR):0.414;95%confidence interval(95%CI):0.190-0.899;P=0.012]and weight gain(OR:0.187;95%CI:0.050-0.693;P=0.026)were less likely to have NASH resolution.Among patients without NASH at baseline,22(3.7%)developed NASH.Baseline BMI≥23 kg/m2(OR:12.506;95%CI:2.813-55.606;P=0.001)and weight gain(OR:5.126;95%CI:1.674-15.694;P=0.005)were predictors of incident NASH.Conclusions:Lower BMI and weight reduction but not virologic factors determine NASH resolution in CHB.The value of weight management in CHB patients during antiviral treatment deserves further evaluation. 展开更多
关键词 Nonalcoholic steatohepatitis Hepatitis b NASH resolution Antiviral treatment weight management
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Spatial Downscaling of the Tropical Rainfall Measuring Mission Precipitation Using Geographically Weighted Regression Kriging over the Lancang River Basin, China 被引量:6
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作者 LI Yungang ZHANG Yueyuan +2 位作者 HE Daming LUO Xian JI Xuan 《Chinese Geographical Science》 SCIE CSCD 2019年第3期446-462,共17页
Satellite-based precipitation products have been widely used to estimate precipitation, especially over regions with sparse rain gauge networks. However, the low spatial resolution of these products has limited their ... Satellite-based precipitation products have been widely used to estimate precipitation, especially over regions with sparse rain gauge networks. However, the low spatial resolution of these products has limited their application in localized regions and watersheds.This study investigated a spatial downscaling approach, Geographically Weighted Regression Kriging(GWRK), to downscale the Tropical Rainfall Measuring Mission(TRMM) 3 B43 Version 7 over the Lancang River Basin(LRB) for 2001–2015. Downscaling was performed based on the relationships between the TRMM precipitation and the Normalized Difference Vegetation Index(NDVI), the Land Surface Temperature(LST), and the Digital Elevation Model(DEM). Geographical ratio analysis(GRA) was used to calibrate the annual downscaled precipitation data, and the monthly fractions derived from the original TRMM data were used to disaggregate annual downscaled and calibrated precipitation to monthly precipitation at 1 km resolution. The final downscaled precipitation datasets were validated against station-based observed precipitation in 2001–2015. Results showed that: 1) The TRMM 3 B43 precipitation was highly accurate with slight overestimation at the basin scale(i.e., CC(correlation coefficient) = 0.91, Bias = 13.3%). Spatially, the accuracies of the upstream and downstream regions were higher than that of the midstream region. 2) The annual downscaled TRMM precipitation data at 1 km spatial resolution obtained by GWRK effectively captured the high spatial variability of precipitation over the LRB. 3) The annual downscaled TRMM precipitation with GRA calibration gave better accuracy compared with the original TRMM dataset. 4) The final downscaled and calibrated precipitation had significantly improved spatial resolution, and agreed well with data from the validated rain gauge stations, i.e., CC = 0.75, RMSE(root mean square error) = 182 mm, MAE(mean absolute error) = 142 mm, and Bias = 0.78%for annual precipitation and CC = 0.95, RMSE = 25 mm, MAE = 16 mm, and Bias = 0.67% for monthly precipitation. 展开更多
关键词 PRECIPITATION Tropical Rainfall Measuring Mission(TRMM) 3b43 Geographically weighted Regression Kriging(GWRK) SPATIAL DOWNSCALING the Lancang River basin China
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B Vitamins Can Reduce Body Weight Gain by Increasing Metabolism-related Enzyme Activities in Rats Fed on a High-Fat Diet 被引量:2
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作者 Ying ZHENG Ai-guo MA +4 位作者 Ming-ci ZHENG Qiu-zhen WANG Hui LIANG Xiu-xia HAN Evert G.Schouten 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2018年第1期174-183,共10页
B vitamins are enzyme cofactors that play an important role in energy metabolism.The aim of this study was to elucidate whether B vitamin administration can reduce body weight(BW)gain by improving energy metabolism-re... B vitamins are enzyme cofactors that play an important role in energy metabolism.The aim of this study was to elucidate whether B vitamin administration can reduce body weight(BW)gain by improving energy metabolism-related enzyme activities in rats fed on a highfat diet.Fifty rats were randomly assigned to one of the following five groups:control group(C),including rats fed on standard rat chow;four treatment groups(H0,H1,H2,and H3),in which rats were fed on a high-fat diet.Rats in the H1 group were treated daily with 100 mg/kg BW thiamine(VB1),100 mg/kg BW riboflavin(VB2),and 250 mg/kg BW niacin(VPP);rats in the H2 group were treated daily with 100 mg/kg BW pyridoxine(VB6),100 mg/kg BW cobalamin(VB12),and 5 mg/kg BW folate(FA);and rats in the H3 group were treated daily with all of the B vitamins administered to the H1 and H2 groups.After 12 weeks,the BW gains from the initial value were 154.5±58.4 g and 159.1±53.0 g in the H1 and C groups,respectively,which were significantly less than the changes in the H0 group(285.2±14.8 g,P〈0.05).In the H0 group,the plasma total cholesterol(CHO)and triglyceride(TG)levels were 1.59±0.30 mmol/L and 1.55±0.40 mmol/L,respectively,which were significantly greater than those in the H1 group(1.19±0.18 mmol/L and 0.76±0.34 mmol/L,respectively,P〈0.05).The activities of transketolase(TK),glutathione reductase,and Na^+/K^+adenosine triphosphatase were significantly increased in the B vitamin-treated groups and were significantly greater than those in the H0 group(P〈0.05).Furthermore,the glucose-6-phosphate dehydrogenase,pyruvic acid kinase,and succinate dehydrogenase activities also were increased after treatment with B vitamins.Supplementation with B vitamins could effectively reduce BW gain and plasma levels of lipids by improving energy metabolism-related enzyme activities in rats,thus possibly providing potential benefits to humans. 展开更多
关键词 b vitamins ObESITY body weight gain enzyme activities RATS
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Optimal b value of diffusion-weighted imaging on a 3.0T magnetic resonance scanner in Crohn's disease 被引量:4
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作者 Qi Feng Yun-Qi Yan +2 位作者 Jiong Zhu Jin-Lu Tong Jian-Rong Xu 《World Journal of Gastroenterology》 SCIE CAS 2014年第35期12621-12627,共7页
AIM: To determine the optimal b value of diffusion-weighted imaging for detecting active inflammation in Crohn&#x02019;s disease.
关键词 Crohn’ s disease Diffusion-weighted imaging b value Magnetic resonance image 3.0 Tesla
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The Impact of Third Trimester Maternal Serum Vitamin B12 and Folate Status on Fetal Birth Weight. Is Maternal Serum Homocysteine a Predictor of Low Birth Weight Infants? 被引量:1
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作者 Mohamed Abdelaziz Youssry Ahmed Mohamed Radwan +1 位作者 Mohamed Amin Gebreel Tabarak Ahmed Patel 《Open Journal of Obstetrics and Gynecology》 2017年第11期1102-1115,共14页
Objective: The aim of this study is to evaluate vitamin B12, folate, and homocysteine status in pregnant women in the third trimester of pregnancy and their relationship to fetal birth weight and their correlation to ... Objective: The aim of this study is to evaluate vitamin B12, folate, and homocysteine status in pregnant women in the third trimester of pregnancy and their relationship to fetal birth weight and their correlation to corresponding neonatal cord blood levels, and in addition, to evaluate the possibility of maternal serum homocysteine level as a predictor of low birth weight infants. Subjects and Methods: In this cross-sectional study, a total of two hundred pregnant women in third trimester (≥28 weeks) were recruited. After a detailed obstetrical and medical history, and clinical assessment, participants were subdivided into two groups: Group (A)—pregnant women who delivered average birth weight (ABW) infants and Group (B) for those who delivered low birth weight (LBW) infants between completed 37 and 42 weeks. Results: Vitamin B12 deficiency was observed in 24.1% of the total cohort. The mean vitamin B12 level was significantly lower in group (B) compared to group (A) (195.2 ± 38.9 vs. 225.9 ± 66.59 respectively P = 0.008). The mean level of homocysteine for women in group (B) was significantly higher than those determined from women in group (A) (9.10 ± 5.9 vs. 7.6 ± 3.83 respectively, P = 0.042). On the other hand, the mean folate levels showed statistically insignificant differences between both groups. The mean cord vitamin B12 level was significantly lower in LBW infants in comparison to ABW infants (277 ± 61.93 vs. 312.03 ± 81.87 respectively, P = 0.015), while the mean level of cord homocysteine for LBW infants was significantly higher than those levels determined from ABW infants (7.9 ± 3.79 vs. 6.6 ± 2.09 respectively P = 0.0049). Conclusion: Maternal micronutrients particularly cobalamin deficiency could be significant risk for LBW infants. Hyperhomocysteinemia has been shown to be a predictor for adverse pregnancy outcomes particularly LBW. 展开更多
关键词 Low bIRTH weight VITAMIN b12 HOMOCYSTEINE
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Weighted ebyev-Ostrowski type inequalities
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作者 Arif Rafiq Nazir Ahmad Mir Farooq Ahmad 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第7期901-906,共6页
In account of the famous Cebysev inequality, a rich theory has appeared in the literature. We establish some new weighted Cebysev type integral inequalities. Our proofs are of independent interest and provide new esti... In account of the famous Cebysev inequality, a rich theory has appeared in the literature. We establish some new weighted Cebysev type integral inequalities. Our proofs are of independent interest and provide new estimates on these types of inequalities. 展开更多
关键词 Cebysev type inequalities L∞ (a b spaces absolutely continuous functions weight functions
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基于Critic权重法多目标优化汽车B柱上饰板注塑成型工艺 被引量:1
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作者 张文超 吴迪 +4 位作者 王明伟 李小虎 崔恩铭 周纪委 叶星辉 《工程塑料应用》 CAS CSCD 北大核心 2024年第4期83-88,共6页
为解决汽车B柱上饰板注塑成型过程中出现的体积收缩和翘曲变形等缺陷问题,利用Moldex3D软件,采用滑石粉改性聚丙烯材料对其注塑成型过程进行模拟。以注射时间、熔体温度、模具温度、保压压力、保压时间为变量,体积收缩率和Z方向(产品脱... 为解决汽车B柱上饰板注塑成型过程中出现的体积收缩和翘曲变形等缺陷问题,利用Moldex3D软件,采用滑石粉改性聚丙烯材料对其注塑成型过程进行模拟。以注射时间、熔体温度、模具温度、保压压力、保压时间为变量,体积收缩率和Z方向(产品脱模方向)的翘曲变形为目标,设计16组正交实验。利用Critic权重法对二者进行权重计算,并通过计算综合评分将多目标优化转化为单目标优化;最终通过计算综合评分的极差分析得到五个工艺参数的影响大小排序为:保压压力>模具温度>充填时间>熔体温度>保压时间,最优成型工艺参数组合为充填时间为2 s、熔体温度为240℃、模具温度为30℃、保压压力为70 MPa、保压时间为8 s。将最优成型工艺参数组合进行模拟,得到该产品的体积收缩率为5.901%,Z方向翘曲变形量为1.75 mm。与初始分析结果相比,体积收缩率降低了12.2%,Z方向翘曲变形量减小了9.04%。通过实际试模验证,产品充填完全,质量良好,符合生产要求。 展开更多
关键词 汽车b柱上饰板 MOLDEX3D 正交试验 Critic权重法 工艺参数优化
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Weighted Bergman Spaces on Bounded Symmetric Domains
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作者 王雄亮 刘太顺 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第1期36-44,共9页
On bounded symmetric domain Ω of C^n, we investigate the properties of functions in weighted Bergman spaces A^P(Ω,dvs) for 0 〈 p ≤ +∞ and -1 〈 s 〈 4-∞. Based on the estimate of Bergman kernel, we obtain som... On bounded symmetric domain Ω of C^n, we investigate the properties of functions in weighted Bergman spaces A^P(Ω,dvs) for 0 〈 p ≤ +∞ and -1 〈 s 〈 4-∞. Based on the estimate of Bergman kernel, we obtain some characterizations of functions in A^P(Ω, dvs) in terms of a class of linear operators D^αB. Making use of these characterizations, we extend A^P(Ω,dvs) to the weighted Bergman spaces Aα^p,B(Ω,dvs) in a very natural way for 1 〈 p 〈 4-∞ and any real number s, that is, -∞ 〈 s 〈 +∞. This unified treatment covers some classical Bergman spaces, Besov spaces and Bloch spaces. Meanwhile, the boundedness of Bergman projection operators on Aα^P,β(Ω, dvs) and the dual of Aα^P,B(Ω, dvs) are given. 展开更多
关键词 bounded symmetric domains linear operator D^αb weighted bergman space A^P Ω dvs) weighted bergman space Aα^p β (Ω dvs DUALITY
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Differentiation between Benign and Malignant Breast Lesions Using ADC on Diffusion-Weighted Imaging at 3.0 T 被引量:1
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作者 Vikash Kr Gupta Wanhua Liu +2 位作者 Rui Wang Yuanyuan Ye Jing Jiang 《Open Journal of Radiology》 2016年第1期1-9,共9页
Aim: To investigate the diagnostic efficiency of apparent diffusion coefficient value (ADC) in differentiating benign from malignant breast lesions at 3.0 T diffusion-weighted imaging with different pair of b value. M... Aim: To investigate the diagnostic efficiency of apparent diffusion coefficient value (ADC) in differentiating benign from malignant breast lesions at 3.0 T diffusion-weighted imaging with different pair of b value. Methods: Total 110 patients with 107 lesions (44 benign and 63 malignant) were selected for our study with five different b-values 0, 400, 800, 1200 and 1600 s/mm<sup>2</sup>. ADC values were calculated using different pairs of b values. The cut-off ADC values and diagnostic efficiency were evaluated by receiver operating characteristic analysis. Comparison of Mean ADC value for breast lesions was determined by using independent sample t test. ROC curves were used for diagnostic efficiency of ADC using different pairs of b values. Results: With increase of b value, mean ADC value decreases. The mean ADC values for benign were 1.73 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 400, 1.57 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 800, 1.43 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 1200 and 1.30 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 1600 s/mm<sup>2</sup>. The mean ADC values for the malignant breast lesion were 1.21 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 400, 1.06 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 800, 0.94 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 1200 and 0.86 × 10<sup>-3</sup> mm<sup>2</sup>/s for b 0 and 1600 s/mm<sup>2</sup>. ADC diagnostic efficiency for benign and malignant lesion for all the pair of b value combination was significant (p > 0.05). The sensitivity, specificity, PPV, NPV and accuracy were 80.95%, 90.9%, 92.72%, 76.92%, 85.04% for b 0 and 400;84.12%, 90.9%, 92.98%, 80%, 86.91% for b 0 and 800;84.12%, 90.9%, 92.98%, 80%, 86.91% for b 0 and 1200;84.12%, 90.9%, 92.98%, 80%, 86.91% for b 0 and 1600 s/mm<sup>2</sup> respectively. Conclusion: DWI is effective in differentiating benign and malignant breast lesion at 3.0 Tesla using ADC with higher b value combination. 展开更多
关键词 Diffusion-weighted Magnetic Resonance Imaging b-VALUES Apparent Diffusion Coefficient breast Lesion
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基于航迹质量评估的雷达和ADS-B数据融合方法 被引量:1
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作者 张丹妍 史达亮 熊伟 《航空工程进展》 CSCD 2024年第2期173-178,共6页
雷达和广播式自动相关监视系统(ADS-B)的数据融合是监视“黑飞”无人机和飞鸟等目标的有效手段,然而两种传感器跟踪性能差异较大且易波动,会导致融合精度下降。提出一种基于航迹质量评估的雷达和ADS-B数据融合方法,首先量化评估局部航... 雷达和广播式自动相关监视系统(ADS-B)的数据融合是监视“黑飞”无人机和飞鸟等目标的有效手段,然而两种传感器跟踪性能差异较大且易波动,会导致融合精度下降。提出一种基于航迹质量评估的雷达和ADS-B数据融合方法,首先量化评估局部航迹精度、数据更新次数和传感器测量误差对局部航迹质量的影响;其次综合计算局部航迹的质量加权因子,基于分布式融合结构完成异步航迹融合处理;最后通过仿真实验和应用对方法的可行性和有效性进行验证。结果表明:本文提出的融合方法能有效提高融合跟踪精度,在传感器跟踪性能出现波动的情况下,跟踪误差均优于传统航迹融合方法。 展开更多
关键词 航迹融合 加权融合 航迹质量 雷达 ADS-b
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血浆N末端B型钠尿肽前体对中重度支气管肺发育不良的预测价值
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作者 刘素佳 刘勇乐 +3 位作者 薛恒 谢瑛玲 杨长仪 修文龙 《中国卫生标准管理》 2024年第14期27-31,共5页
目的探讨血浆N末端B型钠尿肽前体(N-terminal pro-B-type natriuretic peptide,NTproBNP)在预测中重度支气管肺发育不良(bronchopulmonary dysplasia,BPD)风险中的临床价值。方法采用前瞻观察性研究方法,选择2021年6月—2022年12月福建... 目的探讨血浆N末端B型钠尿肽前体(N-terminal pro-B-type natriuretic peptide,NTproBNP)在预测中重度支气管肺发育不良(bronchopulmonary dysplasia,BPD)风险中的临床价值。方法采用前瞻观察性研究方法,选择2021年6月—2022年12月福建省妇幼保健院新生儿科收治的胎龄<30周极/超早产儿95例。分别于出生后第1、7、14、21天检测NTproBNP水平并收集住院期间基本资料,根据美国国家儿童健康与人类发展研究所(National Institute of Child Health and Human Development,NICHD)诊断标准,分为无-轻度BPD组(n=74)和中-重度BPD组(n=21)。比较2组不同时间点NTproBNP水平。结果中-重度BPD组胎龄、出生体质量均低于无-轻度BPD组(P<0.05);中-重度BPD组胎膜早破>18 h、≥3级新生儿呼吸窘迫综合征(respiratory distress syndrome,RDS)、有创机械通气时间>7 d、症状性动脉导管未闭(symptomatic patent ductus arteriosus,sPDA)、晚发型败血症、早产儿视网膜病(retinopathy of prematurity,ROP)的发生率均高于无-轻度BPD组,差异有统计学意义(P<0.05)。无-轻度BPD组NTproBNP水平在出生后第1天最高,中-重度BPD组NTproBNP水平在出生后第7天最高,随后逐渐降低。中-重度BPD组各时间点NTproBNP水平均高于无-轻度BPD组,差异有统计学意义(P<0.05)。出生后第1天NTproBNP水平为5631.52 pg/mL,是中重度BPD最佳预测参考值,受试者工作特征(receiver operating characteristic,ROC)曲线下面积为0.89(95%CI0.83~0.95),诊断准确性为85.71%。结论出生后第1天NTproBNP水平有助于早期预测中重度BPD发病风险,动态监测NTproBNP趋势可能对疾病防治提供一定参考价值。 展开更多
关键词 N末端b型钠尿肽前体 支气管肺发育不良 极低出生体质量 婴儿 标志物 预测
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Diffusion-weighted Single-shot Echo Planar MR Imaging of Normal Human Prostate Using Different b Values
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作者 石浩军 孔祥泉 +3 位作者 冯敢生 徐海波 刘定西 于群 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2008年第6期737-740,共4页
This study examined the effect of different b values on diffusion-weighted MR imaging (DWI) of human prostate by using single-shot spin echo echo planar imaging (SE-EPI) sequences, observed the normal appearances ... This study examined the effect of different b values on diffusion-weighted MR imaging (DWI) of human prostate by using single-shot spin echo echo planar imaging (SE-EPI) sequences, observed the normal appearances and measured apparent diffusion coefficient (ADC) values in anatomical regions of normal prostate. Twenty-four healthy volunteers (mean age: 32 y) were studied by using a 1.5T system with a phased array surface multicoil. Two kinds of single-shot SE-EPI sequence were used to perform DWI in the prostate in volunteers, with five b values being 0, 30, 300, 500 to 1000 s/mm2. The image quality with different imaging parameters was analyzed and the ADC values in anatomical regions of normal prostate were measured. DWI of prostate was successfully obtained in all volunteers. The images were of good quality, without artifacts containing pixels within the prostate. The contrast was good between the different anatomical regions of the prostatic gland, i.e., the peripheral zone (PZ), which exhibited higher signal intensity, and the central gland (CG). Signal intensity contrast was related to the magnitude of b values. The ADC values in PZ and CG were (1.27±0.22)×10-3 mm2/s and (1.01±0.17)×10-3 mm2/s,respectively. The ADC values were found to be significantly higher in PZ than in CG (P〈0.05, paired t-test). Significant differences were found between the slice-selecting component and both the read-out and phase-encoding components of the ADC values. It is concluded that SE-EPI is a suitable DWI sequence for human prostate. The contrast between PZ and CG is good when b values are low, while the diffusion and ADC values are accurate when b values are high. ADC values are higher in PZ than in CG in normal prostate. Diffusional anisotropy is present in normal prostatic tissue. 展开更多
关键词 PROSTATE magnetic resonance imaging diffusion-weighted imaging b value apparentdiffusion coefficient
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多b值DWI联合HR-T_(2)WI在直肠癌术前分期及环周切缘评估中的应用
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作者 郭新 陈芳 +4 位作者 黄从坤 卞志伟 王康 周坤生 张超 《医学影像学杂志》 2024年第7期78-81,85,共5页
目的 探讨多b值扩散加权成像(DWI)联合高分辨率T2加权成像(HR-T2WI)在直肠癌术前分期及环周切缘(CRM)评估价值。方法 选取80例经病理确诊为直肠癌患者,术前均接受多b值DWI、HR-T2WI检查,比较不同T、N分期及CRM性质患者多b值下表观弥散系... 目的 探讨多b值扩散加权成像(DWI)联合高分辨率T2加权成像(HR-T2WI)在直肠癌术前分期及环周切缘(CRM)评估价值。方法 选取80例经病理确诊为直肠癌患者,术前均接受多b值DWI、HR-T2WI检查,比较不同T、N分期及CRM性质患者多b值下表观弥散系数(ADC)差异。以病理组织学检查为金标准,采用Kappa一致性检验多b值DWI联合HR-T2WI诊断结果与病理组织学诊断结果的一致性。结果 T1分期6例,T2分期20例,T3分期32例,T4分期22例;N0分期41例,N1分期23例,N2分期16例;CRM阴性49例,阳性31例。多b值下T1分期患者ADC高于T2、T3、T4分期,且T2分期高于T3、T4分期,T3分期高于T4分期,差异有统计学意义(P<0.05)。多b值下N0分期患者ADC高于N1、N2分期,N1分期高于N2分期,差异均有统计学意义(P<0.05);CRM阴性ADC高于阳性,差异有统计学意义(P<0.05)。HR-T2WI诊断4例T1分期,22例T2分期,31例T3分期,23例T4分期。HR-T2WI检出36例N0分期,28例N1分期,16例N2分期。经Kappa一致性检验显示,HR-T2WI诊断T分期、N分期、CRM性质结果与病理组织学结果存在较强一致性(Kappa=0.730、0.781、0.688,P<0.001)。多b值DWI联合HR-T2WI诊断5例T1分期,23例T2分期,31例T3分期,21例T4分期。多b值DWI联合HR-T2WI诊断39例N0分期,24例N1分期,17例N2分期。结论 多b值DWI联合HR-T2WI对直肠癌术前分期、CRM性质具有良好的诊断价值。 展开更多
关键词 扩散加权成像 b 高分辨率 直肠癌 环周切缘
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多胎B超在湖羊繁殖体系中的应用
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作者 卞苏舒 余波 +4 位作者 蓝徐民 叶峰 沈佳栾 钱定海 罗学明 《浙江农业科学》 2024年第7期1695-1699,共5页
文章结合湖羊繁殖工作中母羊妊娠鉴定重要环节,引进英国BCF生产的Ovi-Scan便携式兽用多胎B超,辅助繁殖人员及时准确快速检查配种母羊怀孕状况,通过对406只成年母羊、223只青年母羊、184只复配母羊进行多胎B超妊娠检查,B超孕检受胎率分... 文章结合湖羊繁殖工作中母羊妊娠鉴定重要环节,引进英国BCF生产的Ovi-Scan便携式兽用多胎B超,辅助繁殖人员及时准确快速检查配种母羊怀孕状况,通过对406只成年母羊、223只青年母羊、184只复配母羊进行多胎B超妊娠检查,B超孕检受胎率分别达到80.05%、82.96%和69.56%,准确度平均达到99.34%;母羊怀孕3羔及以上多胎B超妊娠检查准确度达到95.39%;3羔及以上母羊分娩152只,产羔463只,羔羊平均初生重3.27 kg,同比提高4.81%。通过多胎B超使用,显著提高母羊孕检揭发率,并对检出空怀母羊及时配种,同时对检出怀孕3羔及以上母羊分群饲养,有效提高羔羊初生重,提高湖羊母羊繁殖效率。 展开更多
关键词 湖羊 多胎b 复配受胎率 羔羊初生重
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高b值弥散加权成像在缺血性中风超急性期诊断中的价值
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作者 甘利伟 郑欢露 +4 位作者 胡吉学 胡盼 李俊帆 张雪琴 蒲云学 《保健医学研究与实践》 2024年第1期73-77,共5页
目的探讨高b值磁共振弥散加权成像(DWI)及表观弥散系数(ADC)值在缺血性中风(AIS)超急性期(发病时间<6 h)诊断中的应用价值,以期为临床治疗提供参考。方法选取2020年6月—2023年2月在重庆市北碚区中医院经临床确诊和治疗痊愈或好转的... 目的探讨高b值磁共振弥散加权成像(DWI)及表观弥散系数(ADC)值在缺血性中风(AIS)超急性期(发病时间<6 h)诊断中的应用价值,以期为临床治疗提供参考。方法选取2020年6月—2023年2月在重庆市北碚区中医院经临床确诊和治疗痊愈或好转的AIS超急性期患者34例为研究对象。34例患者均完成高b值(b值=2000 s/mm^(2))、常规b值(b值=1000 s/mm^(2))DWI扫描,将2组DWI图像分为高b值组和常规b值组,分析2组图像的DWI影像特点,并对ADC图进行定量分析。结果高、常规b值组显示病灶分别为98、74个。所研究病例T1WI均呈等或稍低信号、T2WI和T2-Flair呈等或稍高信号,无特异性;高b值组病灶DWI呈中等、明显高信号,常规b值组病灶DWI呈轻度、中等高信号,且高b值组病灶边界显示更清楚。高、常规b值组图像的ADC值比较,病变区ADC值在高b值组更低,2组差异有统计学意义(P<0.05),健侧对称区ADC值也在高b值组更低,2组差异也具有统计学意义(P<0.05);同一b值下的ADC值比较,病变区与健侧对称区ADC值差异均具有统计学意义(P<0.05)。高b值组图像敏感度为100.0%,特异度为82.4%;常规b值组,敏感度为100.0%,特异度为76.5%。高b值组图像SNR、CNR均高于常规b值组,差异均有统计学意义(P<0.05)。结论在临床工作中,采用高b值DWI扫描可以提高AIS超急性期病灶的检出率,并且能使病灶影像质量达到更佳的效果。所以,高b值DWI对超急性期AIS的诊断价值优于常规b值DWI,可能值得临床运用推广。 展开更多
关键词 缺血性中风 超急性期 磁共振成像 弥散加权成像 b
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